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Diffstat (limited to 'src/test/net_peer_eviction_tests.cpp')
| -rw-r--r-- | src/test/net_peer_eviction_tests.cpp | 574 |
1 files changed, 574 insertions, 0 deletions
diff --git a/src/test/net_peer_eviction_tests.cpp b/src/test/net_peer_eviction_tests.cpp new file mode 100644 index 0000000000..4bfd487b86 --- /dev/null +++ b/src/test/net_peer_eviction_tests.cpp @@ -0,0 +1,574 @@ +// Copyright (c) 2021 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <netaddress.h> +#include <net.h> +#include <test/util/net.h> +#include <test/util/setup_common.h> + +#include <boost/test/unit_test.hpp> + +#include <algorithm> +#include <functional> +#include <optional> +#include <unordered_set> +#include <vector> + +BOOST_FIXTURE_TEST_SUITE(net_peer_eviction_tests, BasicTestingSetup) + +std::vector<NodeEvictionCandidate> GetRandomNodeEvictionCandidates(const int n_candidates, FastRandomContext& random_context) +{ + std::vector<NodeEvictionCandidate> candidates; + for (int id = 0; id < n_candidates; ++id) { + candidates.push_back({ + /* id */ id, + /* nTimeConnected */ static_cast<int64_t>(random_context.randrange(100)), + /* m_min_ping_time */ std::chrono::microseconds{random_context.randrange(100)}, + /* nLastBlockTime */ static_cast<int64_t>(random_context.randrange(100)), + /* nLastTXTime */ static_cast<int64_t>(random_context.randrange(100)), + /* fRelevantServices */ random_context.randbool(), + /* fRelayTxes */ random_context.randbool(), + /* fBloomFilter */ random_context.randbool(), + /* nKeyedNetGroup */ random_context.randrange(100), + /* prefer_evict */ random_context.randbool(), + /* m_is_local */ random_context.randbool(), + /* m_network */ ALL_NETWORKS[random_context.randrange(ALL_NETWORKS.size())], + }); + } + return candidates; +} + +// Create `num_peers` random nodes, apply setup function `candidate_setup_fn`, +// call ProtectEvictionCandidatesByRatio() to apply protection logic, and then +// return true if all of `protected_peer_ids` and none of `unprotected_peer_ids` +// are protected from eviction, i.e. removed from the eviction candidates. +bool IsProtected(int num_peers, + std::function<void(NodeEvictionCandidate&)> candidate_setup_fn, + const std::unordered_set<NodeId>& protected_peer_ids, + const std::unordered_set<NodeId>& unprotected_peer_ids, + FastRandomContext& random_context) +{ + std::vector<NodeEvictionCandidate> candidates{GetRandomNodeEvictionCandidates(num_peers, random_context)}; + for (NodeEvictionCandidate& candidate : candidates) { + candidate_setup_fn(candidate); + } + Shuffle(candidates.begin(), candidates.end(), random_context); + + const size_t size{candidates.size()}; + const size_t expected{size - size / 2}; // Expect half the candidates will be protected. + ProtectEvictionCandidatesByRatio(candidates); + BOOST_CHECK_EQUAL(candidates.size(), expected); + + size_t unprotected_count{0}; + for (const NodeEvictionCandidate& candidate : candidates) { + if (protected_peer_ids.count(candidate.id)) { + // this peer should have been removed from the eviction candidates + BOOST_TEST_MESSAGE(strprintf("expected candidate to be protected: %d", candidate.id)); + return false; + } + if (unprotected_peer_ids.count(candidate.id)) { + // this peer remains in the eviction candidates, as expected + ++unprotected_count; + } + } + + const bool is_protected{unprotected_count == unprotected_peer_ids.size()}; + if (!is_protected) { + BOOST_TEST_MESSAGE(strprintf("unprotected: expected %d, actual %d", + unprotected_peer_ids.size(), unprotected_count)); + } + return is_protected; +} + +BOOST_AUTO_TEST_CASE(peer_protection_test) +{ + FastRandomContext random_context{true}; + int num_peers{12}; + + // Expect half of the peers with greatest uptime (the lowest nTimeConnected) + // to be protected from eviction. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = false; + c.m_network = NET_IPV4; + }, + /* protected_peer_ids */ {0, 1, 2, 3, 4, 5}, + /* unprotected_peer_ids */ {6, 7, 8, 9, 10, 11}, + random_context)); + + // Verify in the opposite direction. + BOOST_CHECK(IsProtected( + num_peers, [num_peers](NodeEvictionCandidate& c) { + c.nTimeConnected = num_peers - c.id; + c.m_is_local = false; + c.m_network = NET_IPV6; + }, + /* protected_peer_ids */ {6, 7, 8, 9, 10, 11}, + /* unprotected_peer_ids */ {0, 1, 2, 3, 4, 5}, + random_context)); + + // Test protection of onion, localhost, and I2P peers... + + // Expect 1/4 onion peers to be protected from eviction, + // if no localhost or I2P peers. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.m_is_local = false; + c.m_network = (c.id == 3 || c.id == 8 || c.id == 9) ? NET_ONION : NET_IPV4; + }, + /* protected_peer_ids */ {3, 8, 9}, + /* unprotected_peer_ids */ {}, + random_context)); + + // Expect 1/4 onion peers and 1/4 of the other peers to be protected, + // sorted by longest uptime (lowest nTimeConnected), if no localhost or I2P peers. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = false; + c.m_network = (c.id == 3 || c.id > 7) ? NET_ONION : NET_IPV6; + }, + /* protected_peer_ids */ {0, 1, 2, 3, 8, 9}, + /* unprotected_peer_ids */ {4, 5, 6, 7, 10, 11}, + random_context)); + + // Expect 1/4 localhost peers to be protected from eviction, + // if no onion or I2P peers. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.m_is_local = (c.id == 1 || c.id == 9 || c.id == 11); + c.m_network = NET_IPV4; + }, + /* protected_peer_ids */ {1, 9, 11}, + /* unprotected_peer_ids */ {}, + random_context)); + + // Expect 1/4 localhost peers and 1/4 of the other peers to be protected, + // sorted by longest uptime (lowest nTimeConnected), if no onion or I2P peers. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id > 6); + c.m_network = NET_IPV6; + }, + /* protected_peer_ids */ {0, 1, 2, 7, 8, 9}, + /* unprotected_peer_ids */ {3, 4, 5, 6, 10, 11}, + random_context)); + + // Expect 1/4 I2P peers to be protected from eviction, + // if no onion or localhost peers. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.m_is_local = false; + c.m_network = (c.id == 2 || c.id == 7 || c.id == 10) ? NET_I2P : NET_IPV4; + }, + /* protected_peer_ids */ {2, 7, 10}, + /* unprotected_peer_ids */ {}, + random_context)); + + // Expect 1/4 I2P peers and 1/4 of the other peers to be protected, + // sorted by longest uptime (lowest nTimeConnected), if no onion or localhost peers. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = false; + c.m_network = (c.id == 4 || c.id > 8) ? NET_I2P : NET_IPV6; + }, + /* protected_peer_ids */ {0, 1, 2, 4, 9, 10}, + /* unprotected_peer_ids */ {3, 5, 6, 7, 8, 11}, + random_context)); + + // Tests with 2 networks... + + // Combined test: expect having 1 localhost and 1 onion peer out of 4 to + // protect 1 localhost, 0 onion and 1 other peer, sorted by longest uptime; + // stable sort breaks tie with array order of localhost first. + BOOST_CHECK(IsProtected( + 4, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 4); + c.m_network = (c.id == 3) ? NET_ONION : NET_IPV4; + }, + /* protected_peer_ids */ {0, 4}, + /* unprotected_peer_ids */ {1, 2}, + random_context)); + + // Combined test: expect having 1 localhost and 1 onion peer out of 7 to + // protect 1 localhost, 0 onion, and 2 other peers (3 total), sorted by + // uptime; stable sort breaks tie with array order of localhost first. + BOOST_CHECK(IsProtected( + 7, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 6); + c.m_network = (c.id == 5) ? NET_ONION : NET_IPV4; + }, + /* protected_peer_ids */ {0, 1, 6}, + /* unprotected_peer_ids */ {2, 3, 4, 5}, + random_context)); + + // Combined test: expect having 1 localhost and 1 onion peer out of 8 to + // protect protect 1 localhost, 1 onion and 2 other peers (4 total), sorted + // by uptime; stable sort breaks tie with array order of localhost first. + BOOST_CHECK(IsProtected( + 8, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 6); + c.m_network = (c.id == 5) ? NET_ONION : NET_IPV4; + }, + /* protected_peer_ids */ {0, 1, 5, 6}, + /* unprotected_peer_ids */ {2, 3, 4, 7}, + random_context)); + + // Combined test: expect having 3 localhost and 3 onion peers out of 12 to + // protect 2 localhost and 1 onion, plus 3 other peers, sorted by longest + // uptime; stable sort breaks ties with the array order of localhost first. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 6 || c.id == 9 || c.id == 11); + c.m_network = (c.id == 7 || c.id == 8 || c.id == 10) ? NET_ONION : NET_IPV6; + }, + /* protected_peer_ids */ {0, 1, 2, 6, 7, 9}, + /* unprotected_peer_ids */ {3, 4, 5, 8, 10, 11}, + random_context)); + + // Combined test: expect having 4 localhost and 1 onion peer out of 12 to + // protect 2 localhost and 1 onion, plus 3 other peers, sorted by longest uptime. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id > 4 && c.id < 9); + c.m_network = (c.id == 10) ? NET_ONION : NET_IPV4; + }, + /* protected_peer_ids */ {0, 1, 2, 5, 6, 10}, + /* unprotected_peer_ids */ {3, 4, 7, 8, 9, 11}, + random_context)); + + // Combined test: expect having 4 localhost and 2 onion peers out of 16 to + // protect 2 localhost and 2 onions, plus 4 other peers, sorted by longest uptime. + BOOST_CHECK(IsProtected( + 16, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 6 || c.id == 9 || c.id == 11 || c.id == 12); + c.m_network = (c.id == 8 || c.id == 10) ? NET_ONION : NET_IPV6; + }, + /* protected_peer_ids */ {0, 1, 2, 3, 6, 8, 9, 10}, + /* unprotected_peer_ids */ {4, 5, 7, 11, 12, 13, 14, 15}, + random_context)); + + // Combined test: expect having 5 localhost and 1 onion peer out of 16 to + // protect 3 localhost (recovering the unused onion slot), 1 onion, and 4 + // others, sorted by longest uptime. + BOOST_CHECK(IsProtected( + 16, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id > 10); + c.m_network = (c.id == 10) ? NET_ONION : NET_IPV4; + }, + /* protected_peer_ids */ {0, 1, 2, 3, 10, 11, 12, 13}, + /* unprotected_peer_ids */ {4, 5, 6, 7, 8, 9, 14, 15}, + random_context)); + + // Combined test: expect having 1 localhost and 4 onion peers out of 16 to + // protect 1 localhost and 3 onions (recovering the unused localhost slot), + // plus 4 others, sorted by longest uptime. + BOOST_CHECK(IsProtected( + 16, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 15); + c.m_network = (c.id > 6 && c.id < 11) ? NET_ONION : NET_IPV6; + }, + /* protected_peer_ids */ {0, 1, 2, 3, 7, 8, 9, 15}, + /* unprotected_peer_ids */ {5, 6, 10, 11, 12, 13, 14}, + random_context)); + + // Combined test: expect having 2 onion and 4 I2P out of 12 peers to protect + // 2 onion (prioritized for having fewer candidates) and 1 I2P, plus 3 + // others, sorted by longest uptime. + BOOST_CHECK(IsProtected( + num_peers, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = false; + if (c.id == 8 || c.id == 10) { + c.m_network = NET_ONION; + } else if (c.id == 6 || c.id == 9 || c.id == 11 || c.id == 12) { + c.m_network = NET_I2P; + } else { + c.m_network = NET_IPV4; + } + }, + /* protected_peer_ids */ {0, 1, 2, 6, 8, 10}, + /* unprotected_peer_ids */ {3, 4, 5, 7, 9, 11}, + random_context)); + + // Tests with 3 networks... + + // Combined test: expect having 1 localhost, 1 I2P and 1 onion peer out of 4 + // to protect 1 I2P, 0 localhost, 0 onion and 1 other peer (2 total), sorted + // by longest uptime; stable sort breaks tie with array order of I2P first. + BOOST_CHECK(IsProtected( + 4, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 3); + if (c.id == 4) { + c.m_network = NET_I2P; + } else if (c.id == 2) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV6; + } + }, + /* protected_peer_ids */ {0, 4}, + /* unprotected_peer_ids */ {1, 2}, + random_context)); + + // Combined test: expect having 1 localhost, 1 I2P and 1 onion peer out of 7 + // to protect 1 I2P, 0 localhost, 0 onion and 2 other peers (3 total) sorted + // by longest uptime; stable sort breaks tie with array order of I2P first. + BOOST_CHECK(IsProtected( + 7, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 4); + if (c.id == 6) { + c.m_network = NET_I2P; + } else if (c.id == 5) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV6; + } + }, + /* protected_peer_ids */ {0, 1, 6}, + /* unprotected_peer_ids */ {2, 3, 4, 5}, + random_context)); + + // Combined test: expect having 1 localhost, 1 I2P and 1 onion peer out of 8 + // to protect 1 I2P, 1 localhost, 0 onion and 2 other peers (4 total) sorted + // by uptime; stable sort breaks tie with array order of I2P then localhost. + BOOST_CHECK(IsProtected( + 8, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 6); + if (c.id == 5) { + c.m_network = NET_I2P; + } else if (c.id == 4) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV6; + } + }, + /* protected_peer_ids */ {0, 1, 5, 6}, + /* unprotected_peer_ids */ {2, 3, 4, 7}, + random_context)); + + // Combined test: expect having 4 localhost, 2 I2P, and 2 onion peers out of + // 16 to protect 1 localhost, 2 I2P, and 1 onion (4/16 total), plus 4 others + // for 8 total, sorted by longest uptime. + BOOST_CHECK(IsProtected( + 16, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 6 || c.id > 11); + if (c.id == 7 || c.id == 11) { + c.m_network = NET_I2P; + } else if (c.id == 9 || c.id == 10) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV4; + } + }, + /* protected_peer_ids */ {0, 1, 2, 3, 6, 7, 9, 11}, + /* unprotected_peer_ids */ {4, 5, 8, 10, 12, 13, 14, 15}, + random_context)); + + // Combined test: expect having 1 localhost, 8 I2P and 1 onion peer out of + // 24 to protect 1, 4, and 1 (6 total), plus 6 others for 12/24 total, + // sorted by longest uptime. + BOOST_CHECK(IsProtected( + 24, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 12); + if (c.id > 14 && c.id < 23) { // 4 protected instead of usual 2 + c.m_network = NET_I2P; + } else if (c.id == 23) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV6; + } + }, + /* protected_peer_ids */ {0, 1, 2, 3, 4, 5, 12, 15, 16, 17, 18, 23}, + /* unprotected_peer_ids */ {6, 7, 8, 9, 10, 11, 13, 14, 19, 20, 21, 22}, + random_context)); + + // Combined test: expect having 1 localhost, 3 I2P and 6 onion peers out of + // 24 to protect 1, 3, and 2 (6 total, I2P has fewer candidates and so gets the + // unused localhost slot), plus 6 others for 12/24 total, sorted by longest uptime. + BOOST_CHECK(IsProtected( + 24, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 15); + if (c.id == 12 || c.id == 14 || c.id == 17) { + c.m_network = NET_I2P; + } else if (c.id > 17) { // 4 protected instead of usual 2 + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV4; + } + }, + /* protected_peer_ids */ {0, 1, 2, 3, 4, 5, 12, 14, 15, 17, 18, 19}, + /* unprotected_peer_ids */ {6, 7, 8, 9, 10, 11, 13, 16, 20, 21, 22, 23}, + random_context)); + + // Combined test: expect having 1 localhost, 7 I2P and 4 onion peers out of + // 24 to protect 1 localhost, 2 I2P, and 3 onions (6 total), plus 6 others + // for 12/24 total, sorted by longest uptime. + BOOST_CHECK(IsProtected( + 24, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id == 13); + if (c.id > 16) { + c.m_network = NET_I2P; + } else if (c.id == 12 || c.id == 14 || c.id == 15 || c.id == 16) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV6; + } + }, + /* protected_peer_ids */ {0, 1, 2, 3, 4, 5, 12, 13, 14, 15, 17, 18}, + /* unprotected_peer_ids */ {6, 7, 8, 9, 10, 11, 16, 19, 20, 21, 22, 23}, + random_context)); + + // Combined test: expect having 8 localhost, 4 I2P, and 3 onion peers out of + // 24 to protect 2 of each (6 total), plus 6 others for 12/24 total, sorted + // by longest uptime. + BOOST_CHECK(IsProtected( + 24, [](NodeEvictionCandidate& c) { + c.nTimeConnected = c.id; + c.m_is_local = (c.id > 15); + if (c.id > 10 && c.id < 15) { + c.m_network = NET_I2P; + } else if (c.id > 6 && c.id < 10) { + c.m_network = NET_ONION; + } else { + c.m_network = NET_IPV4; + } + }, + /* protected_peer_ids */ {0, 1, 2, 3, 4, 5, 7, 8, 11, 12, 16, 17}, + /* unprotected_peer_ids */ {6, 9, 10, 13, 14, 15, 18, 19, 20, 21, 22, 23}, + random_context)); +} + +// Returns true if any of the node ids in node_ids are selected for eviction. +bool IsEvicted(std::vector<NodeEvictionCandidate> candidates, const std::unordered_set<NodeId>& node_ids, FastRandomContext& random_context) +{ + Shuffle(candidates.begin(), candidates.end(), random_context); + const std::optional<NodeId> evicted_node_id = SelectNodeToEvict(std::move(candidates)); + if (!evicted_node_id) { + return false; + } + return node_ids.count(*evicted_node_id); +} + +// Create number_of_nodes random nodes, apply setup function candidate_setup_fn, +// apply eviction logic and then return true if any of the node ids in node_ids +// are selected for eviction. +bool IsEvicted(const int number_of_nodes, std::function<void(NodeEvictionCandidate&)> candidate_setup_fn, const std::unordered_set<NodeId>& node_ids, FastRandomContext& random_context) +{ + std::vector<NodeEvictionCandidate> candidates = GetRandomNodeEvictionCandidates(number_of_nodes, random_context); + for (NodeEvictionCandidate& candidate : candidates) { + candidate_setup_fn(candidate); + } + return IsEvicted(candidates, node_ids, random_context); +} + +BOOST_AUTO_TEST_CASE(peer_eviction_test) +{ + FastRandomContext random_context{true}; + + for (int number_of_nodes = 0; number_of_nodes < 200; ++number_of_nodes) { + // Four nodes with the highest keyed netgroup values should be + // protected from eviction. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [number_of_nodes](NodeEvictionCandidate& candidate) { + candidate.nKeyedNetGroup = number_of_nodes - candidate.id; + }, + {0, 1, 2, 3}, random_context)); + + // Eight nodes with the lowest minimum ping time should be protected + // from eviction. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [](NodeEvictionCandidate& candidate) { + candidate.m_min_ping_time = std::chrono::microseconds{candidate.id}; + }, + {0, 1, 2, 3, 4, 5, 6, 7}, random_context)); + + // Four nodes that most recently sent us novel transactions accepted + // into our mempool should be protected from eviction. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [number_of_nodes](NodeEvictionCandidate& candidate) { + candidate.nLastTXTime = number_of_nodes - candidate.id; + }, + {0, 1, 2, 3}, random_context)); + + // Up to eight non-tx-relay peers that most recently sent us novel + // blocks should be protected from eviction. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [number_of_nodes](NodeEvictionCandidate& candidate) { + candidate.nLastBlockTime = number_of_nodes - candidate.id; + if (candidate.id <= 7) { + candidate.fRelayTxes = false; + candidate.fRelevantServices = true; + } + }, + {0, 1, 2, 3, 4, 5, 6, 7}, random_context)); + + // Four peers that most recently sent us novel blocks should be + // protected from eviction. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [number_of_nodes](NodeEvictionCandidate& candidate) { + candidate.nLastBlockTime = number_of_nodes - candidate.id; + }, + {0, 1, 2, 3}, random_context)); + + // Combination of the previous two tests. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [number_of_nodes](NodeEvictionCandidate& candidate) { + candidate.nLastBlockTime = number_of_nodes - candidate.id; + if (candidate.id <= 7) { + candidate.fRelayTxes = false; + candidate.fRelevantServices = true; + } + }, + {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}, random_context)); + + // Combination of all tests above. + BOOST_CHECK(!IsEvicted( + number_of_nodes, [number_of_nodes](NodeEvictionCandidate& candidate) { + candidate.nKeyedNetGroup = number_of_nodes - candidate.id; // 4 protected + candidate.m_min_ping_time = std::chrono::microseconds{candidate.id}; // 8 protected + candidate.nLastTXTime = number_of_nodes - candidate.id; // 4 protected + candidate.nLastBlockTime = number_of_nodes - candidate.id; // 4 protected + }, + {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19}, random_context)); + + // An eviction is expected given >= 29 random eviction candidates. The eviction logic protects at most + // four peers by net group, eight by lowest ping time, four by last time of novel tx, up to eight non-tx-relay + // peers by last novel block time, and four more peers by last novel block time. + if (number_of_nodes >= 29) { + BOOST_CHECK(SelectNodeToEvict(GetRandomNodeEvictionCandidates(number_of_nodes, random_context))); + } + + // No eviction is expected given <= 20 random eviction candidates. The eviction logic protects at least + // four peers by net group, eight by lowest ping time, four by last time of novel tx and four peers by last + // novel block time. + if (number_of_nodes <= 20) { + BOOST_CHECK(!SelectNodeToEvict(GetRandomNodeEvictionCandidates(number_of_nodes, random_context))); + } + + // Cases left to test: + // * "If any remaining peers are preferred for eviction consider only them. [...]" + // * "Identify the network group with the most connections and youngest member. [...]" + } +} + +BOOST_AUTO_TEST_SUITE_END() |